Hexaazatriphenylene has been made previously, but one sequence is rather long and does not suggest any easy way to incorporate the kind of functionality present in hexaazatriphenylene hexanitrile (Nasielski-Hinkens. R.; Benedek-Vamos, M.; Maetens, D.; Nasielski, J.; J. Organometal. Chem., (1981), 217, 179), while another was accomplished only in very low yield (Kohne, B.; Praefcke, K.; Liebigs Ann. Chem., (1985), 522). Precursor materials for preparing the title compound are available commercially, but because of cost or other reasons one may want to prepare various starting materials, e.g. hexaketocyclohexane octahydrate, in-house as will be described later.
High-temperature resistant polymers are known materials with a wide range of present and future applications. Especially desirable for some applications are those polymers with high thermooxidative stability (i.e. they maintain structural integrity when heated to high temperatures in the presence of air or oxygen) and do not undergo significant loss of other physical properties. Illustrative of one such class are the phthalocyanine-type polymers (Keller, T.M.; Griffith, J. R.; J. Flourine Chem. (1979), 13, 315). Another such class of polymers are polyimides, and for high thermooxidative stability noticeably polyimide and like polymeric structures devoid of, or of low content, in their structures of hydrogen present as C-H bonds. Hexaazatriphenylene hexanitrile and its other hexaderivatives described herein offer potential for use, and are useful, for providing improved and new high thermooxidative stable polymers of several different chemical classes. This invention's compounds offer the advantage of compounds whose structure has a hexaazatriphenylene nucleus completely devoid of hydrogen while providing functional groups attached to the nucleus. For some of the invention's compounds, the attached functional groups, especially in the titled hexanitrile, advantageously are devoid completely of hydrogen. In other words, whatever hydrogen is present only is in their functional groups and is removed or removable during incorporation into the useful polymer. Various of the invention's compounds find utility in the preparation of high thermooxidative stable polymers as cross-linking agents or reactants, such as copolymerizing or co-condensation reactants, as additives, as constituents in various polymer formulations for binding metal fillers or for making the polymeric formulation more processable and/or machineable, and the like.
Various of the derivatives of hexaazatriphenylene hexanitrile should be useful as cross-linking agents in thermooxidatively stable polymer synthesis; the complete lack of hydrogens or of aliphatic carbons in, for example, hexaazatriphenylene trisanhydride should afford a resistance to thermal degradation in the presence of air. Co-polymers thusly prepared should bind metal ions owing to phenanthroline-like chelating sites; the potential to make cross-linked inorganic polymers also exists. The title compound itself and/or its monomeric derivatives will certainly be capable of multiple metal ion binding, and the use of a water soluble derivative such as hexaacid could well have intercalating and/or hydrolytic properties in biochemical systems.
With increasing needs to conserve valuable chemicals, including metals, by their isolation and recovery, and also increasing demands that chemical processing liquids, effluents, etc. be cleaned-up and significantly depleted of harmful constituents therein before their disposal, recycling or the like, a providing of new compounds for such applications is highly desirable. Some of the invention's compounds, noticeably the hexaacid, characterized by a structure nucleus of a hexaazatriphenylene moiety provide an unusual affinity for many cations and especially metal cations. This affinity also while not completely understood may be of the nature of chelation, covalent and/or ionic bonding, occlusion, or the like. Depending on the nature of the hexafunctional groups and particular liquids in which the various hexaazatriphenylene compounds are utilized, their specific functional groups can assist and increase the ability to tie-up or bind cations in the liquid. Generally, the metal ion/hexaazatriphenylene complex forms as a solid precipitate, which can be filtered out, or the liquid decanted from, and the cation value (e.g. metal) recovered from the isolated solid by chemical means (e.g. hydrolysis) or physical means (e.g. pyrolysis).